A pitch that is not hit into the field of play is called either a strike or a ball. A batter against whom three strikes are recorded strikes out. A batter against whom four balls are recorded is awarded a base on balls or walk, a free advance to first base. (A batter may also freely advance to first base if the batter's body or uniform is struck by a pitch outside the strike zone, provided the batter does not swing and attempts to avoid being hit.) Crucial to determining balls and strikes is the umpire's judgment as to whether a pitch has passed through the strike zone, a conceptual area above home plate extending from the midpoint between the batter's shoulders and belt down to the hollow of the knee. Any pitch which does not pass through the strike zone is called a ball, unless the batter either swings and misses at the pitch, or hits the pitch into foul territory; an exception generally occurs if the ball is hit into foul territory when the batter already has two strikes, in which case neither a ball nor a strike is called.
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